The present invention relates to a new and improved apparatus for measuring the length of filamentary material, such as a yarn or thread or the like, wound-up at individual locations or stations in a textile machine.
In its more specific aspects, the present invention relates to a new and improved apparatus for measuring the length of filamentary material, such as a yarn or thread or the like, wound up at a number n of individual locations or stations, especially at winding or spinning locations, of a textile machine, which apparatus cooperates with an electronic scanner or interrogation device delivering signals on output lines thereof, namely for each individual winding or spinning location or station a thread running signal, and a reset signal and a read-in signal at the end of each scanning or interrogation cycle.
An e1ectronic scanning or interrogation circuit for monitoring a multitude of running thread locations in a textile machine is described in my aforementioned copending U.S. application Ser. No. 06/470,591, filed Feb. 28, 1983 Pat. No. 4,512,028, and entitled "Electronic Scanner for Monitoring Running Threads at a Multitude of Locations in a Textile Machine". By means of such scanning or interrogation circuit thread ruptures occurring at individual thread running locations or stations of a textile machine can be detected and counted.
In many cases, for example, in automatic winding machines or open-end spinning machines, it is desired to produce yarn or thread packages which always have a constant yarn or thread length. Length cutting devices suitable for this purpose are known, and by means thereof each thread running location and winding location or spinning location is stopped or brought to standstill after the passage of a distinct length of yarn. A particularly simple technique of measuring the length is based upon counting the revolutions of a drum or guide disk about which the yarn is supplied to a wind-up spool as known, for example, from Swiss Pat. No. 568,233, German Pat. No. 2,351,463 and British Pat. No. 1,480,398. The yarn length for each revolution of the drum or disk then results as a function of the diameter thereof.